The present invention relates to a pull tab for a container, such as a beverage container, which can be operated to close the opening in the container after the pull tab has been used to create the opening.
The typical beverage container available on the market today includes a top wall with a score line formed to define a drinking opening. A pull tab is connected to the top wall of the container for pivoting motion about its point of connection for pressing one end of the pull tab into the top wall area inside the boundary of the score line. This motion is effected by pulling the opposite end of the pull tab upwardly with respect to the top wall of the container. This causes rupturing of the score line and pivoting of the enclosed wall portion downwardly into the container.
Pull tabs of the typical construction described above provide no means for sealing the drinking opening once it has been created. In many situations this is not a significant problem. However, there are occasions where it can be desirable to close the drinking opening once it has been created in a manner which at least retards loss of carbonation of the contents or spilling of the contents if the container is accidentally knocked over.
Attempts have been made in the past to construct pull tabs with sealing closures for covering the drinking opening once formed. Such pull tabs and closures for containers are disclosed in the following U.S. Pat. Nos.: 4,077,538; 4,232,797; 4,433,792; 4,442,950; 4,580,692; 4,605,141; 4,720,022; 4,784,283; 4,865,215; and 4,915,290. Many of the constructions disclosed in these patents are rather complicated in construction in that they either include multiple parts or deviate substantially from the typical pull tab presently available. They also require manufacturing procedures quite different from those presently used for forming the typical pull tab.
Of the constructions disclosed in the prior patents, the ones like those in U.S. Pat. Nos. 4,433,792 and 4,605,141 appear closest in construction to the typical pull tab and do include structure for covering the drinking opening once it has been formed. These constructions, however, do not provide any ring-shaped grasping portion on the pull tab as usually included with the conventional pull tab. Further, they require either an engaged relation of the cover in the opening or a hold-down latch for holding the cover sealed against the opening. Also, further dimensional limitations with respect to the spacing between the pivot post for the pull tab and the score line in the container top wall are necessitated in the construction of the '141 patent.